Задача 65: Площадь многоугольника

GetSquareOfPolygon.cs

using System;
					
public class Program
{
	public static double GetSquareOfPolygon(int[] X, int[] Y)
	{
		if (X.Length < 1 && Y.Length < 1 && X.Length != Y.Length)
		{
			throw new Exception("Input data is not correct");
		}
		int length = X.Length;
		
		int[] newX = new int[length + 1];
		int[] newY = new int[length + 1];
		Array.Copy(X, newX, length);
		Array.Copy(Y, newY, length);
		newX[X.Length] = newX[0];
		newY[Y.Length] = newY[0];
		
		// Площадь многоугольника по формуле трапеций
		double S = 0;
		for (int i = 0; i < length; i++)
		{
			S += Math.Abs((newY[i + 1] + newY[i]) * (newX[i + 1] - newX[i])) / 2.0;
		}
		
		return S;
	}	
	
	public static void Main()
	{
		Console.WriteLine("UniLecs");
		int[] X = new int[] { 0, 0, 2 };
		int[] Y = new int[] { 0, 2, 0 };
		Console.WriteLine(string.Format("Answer = {0}", GetSquareOfPolygon(X, Y)));
	}
}